/**
 * crc 报文校验
 */
var CRC = {};

CRC._auchCRCHi = [0x00, 0xC1, 0x81,
  0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00,
  0xC1, 0x81, 0x40, 0x01, 0xC0,
  0x80, 0x41, 0x00, 0xC1, 0x81,
  0x40, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x01,
  0xC0, 0x80, 0x41, 0x00, 0xC1,
  0x81, 0x40, 0x00, 0xC1, 0x81,
  0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01,
  0xC0, 0x80, 0x41, 0x01, 0xC0,
  0x80, 0x41, 0x00, 0xC1, 0x81,
  0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x00,
  0xC1, 0x81, 0x40, 0x01, 0xC0,
  0x80, 0x41, 0x00, 0xC1, 0x81,
  0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00,
  0xC1, 0x81, 0x40, 0x00, 0xC1,
  0x81, 0x40, 0x01, 0xC0, 0x80,
  0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01,
  0xC0, 0x80, 0x41, 0x00, 0xC1,
  0x81, 0x40, 0x00, 0xC1, 0x81,
  0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00,
  0xC1, 0x81, 0x40, 0x00, 0xC1,
  0x81, 0x40, 0x01, 0xC0, 0x80,
  0x41, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x01,
  0xC0, 0x80, 0x41, 0x00, 0xC1,
  0x81, 0x40, 0x00, 0xC1, 0x81,
  0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00,
  0xC1, 0x81, 0x40, 0x01, 0xC0,
  0x80, 0x41, 0x00, 0xC1, 0x81,
  0x40, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x00,
  0xC1, 0x81, 0x40, 0x01, 0xC0,
  0x80, 0x41, 0x01, 0xC0, 0x80,
  0x41, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x00,
  0xC1, 0x81, 0x40, 0x00, 0xC1,
  0x81, 0x40, 0x01, 0xC0, 0x80,
  0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x00,
  0xC1, 0x81, 0x40, 0x01, 0xC0,
  0x80, 0x41, 0x00, 0xC1, 0x81,
  0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00,
  0xC1, 0x81, 0x40
];
CRC._auchCRCLo = [0x00, 0xC0, 0xC1,
  0x01, 0xC3, 0x03, 0x02, 0xC2,
  0xC6, 0x06, 0x07, 0xC7, 0x05,
  0xC5, 0xC4, 0x04, 0xCC, 0x0C,
  0x0D, 0xCD, 0x0F, 0xCF, 0xCE,
  0x0E, 0x0A, 0xCA, 0xCB, 0x0B,
  0xC9, 0x09, 0x08, 0xC8, 0xD8,
  0x18, 0x19, 0xD9, 0x1B, 0xDB,
  0xDA, 0x1A, 0x1E, 0xDE, 0xDF,
  0x1F, 0xDD, 0x1D, 0x1C, 0xDC,
  0x14, 0xD4, 0xD5, 0x15, 0xD7,
  0x17, 0x16, 0xD6, 0xD2, 0x12,
  0x13, 0xD3, 0x11, 0xD1, 0xD0,
  0x10, 0xF0, 0x30, 0x31, 0xF1,
  0x33, 0xF3, 0xF2, 0x32, 0x36,
  0xF6, 0xF7, 0x37, 0xF5, 0x35,
  0x34, 0xF4, 0x3C, 0xFC, 0xFD,
  0x3D, 0xFF, 0x3F, 0x3E, 0xFE,
  0xFA, 0x3A, 0x3B, 0xFB, 0x39,
  0xF9, 0xF8, 0x38, 0x28, 0xE8,
  0xE9, 0x29, 0xEB, 0x2B, 0x2A,
  0xEA, 0xEE, 0x2E, 0x2F, 0xEF,
  0x2D, 0xED, 0xEC, 0x2C, 0xE4,
  0x24, 0x25, 0xE5, 0x27, 0xE7,
  0xE6, 0x26, 0x22, 0xE2, 0xE3,
  0x23, 0xE1, 0x21, 0x20, 0xE0,
  0xA0, 0x60, 0x61, 0xA1, 0x63,
  0xA3, 0xA2, 0x62, 0x66, 0xA6,
  0xA7, 0x67, 0xA5, 0x65, 0x64,
  0xA4, 0x6C, 0xAC, 0xAD, 0x6D,
  0xAF, 0x6F, 0x6E, 0xAE, 0xAA,
  0x6A, 0x6B, 0xAB, 0x69, 0xA9,
  0xA8, 0x68, 0x78, 0xB8, 0xB9,
  0x79, 0xBB, 0x7B, 0x7A, 0xBA,
  0xBE, 0x7E, 0x7F, 0xBF, 0x7D,
  0xBD, 0xBC, 0x7C, 0xB4, 0x74,
  0x75, 0xB5, 0x77, 0xB7, 0xB6,
  0x76, 0x72, 0xB2, 0xB3, 0x73,
  0xB1, 0x71, 0x70, 0xB0, 0x50,
  0x90, 0x91, 0x51, 0x93, 0x53,
  0x52, 0x92, 0x96, 0x56, 0x57,
  0x97, 0x55, 0x95, 0x94, 0x54,
  0x9C, 0x5C, 0x5D, 0x9D, 0x5F,
  0x9F, 0x9E, 0x5E, 0x5A, 0x9A,
  0x9B, 0x5B, 0x99, 0x59, 0x58,
  0x98, 0x88, 0x48, 0x49, 0x89,
  0x4B, 0x8B, 0x8A, 0x4A, 0x4E,
  0x8E, 0x8F, 0x4F, 0x8D, 0x4D,
  0x4C, 0x8C, 0x44, 0x84, 0x85,
  0x45, 0x87, 0x47, 0x46, 0x86,
  0x82, 0x42, 0x43, 0x83, 0x41,
  0x81, 0x80, 0x40
];

CRC.CRC16 = function (buffer) {
  var hi = 0xff;
  var lo = 0xff;
  for (var i = 0; i < buffer.length; i++) {
    var idx = hi ^ buffer[i];
    hi = (lo ^ CRC._auchCRCHi[idx]);
    lo = CRC._auchCRCLo[idx];
  }
  return CRC.padLeft((hi << 8 | lo).toString(16).toUpperCase(), 4, '0');
};

CRC.CRC16RAW = function (buffer0) {
  var buffer = new Uint8Array(buffer0)
  var hi = 0xff;
  var lo = 0xff;
  for (var i = 0; i < buffer.length; i++) {
    var idx = hi ^ buffer[i];
    hi = (lo ^ CRC._auchCRCHi[idx]);
    lo = CRC._auchCRCLo[idx];
  }
  return (lo << 8 | hi);
}

CRC.isArray = function (arr) {
  var type = Object.prototype.toString.call(arr)
  return type === '[object ArrayBuffer]' || type === '[object Array]';
};

CRC.ToCRC16 = function (str) {
  if (CRC.isArray(str)) {
    return CRC.CRC16RAW(str);
  } else {
    return CRC.CRC16(CRC.hexStr2Byte(str));
  }
};

CRC.hexStr2Byte = function (str) {
  var typedArray = new Uint8Array(str.match(/[\da-f]{2}/gi).map(function (h) {
    return parseInt(h, 16);
  }));
  return typedArray
}

CRC.strToByte = function (str) {
  var tmp = str.split(''),
    arr = [];
  for (var i = 0, c = tmp.length; i < c; i++) {
    var j = encodeURI(tmp[i]);
    if (j.length == 1) {
      arr.push(j.charCodeAt());
    } else {
      var b = j.split('%');
      for (var m = 1; m < b.length; m++) {
        arr.push(parseInt('0x' + b[m]));
      }
    }
  }
  return arr;
};

CRC.padLeft = function (s, w, pc) {
  if (pc == undefined) {
    pc = '0';
  }
  for (var i = 0, c = w - s.length; i < c; i++) {
    s = pc + s;
  }
  return s;
};

module.exports = {
  CRC,
}